About 200 people attend a candlelight vigil in Midland, Texas, on Saturday in honor of the people involved in the parade accident there last week that killed four veterans. / Edward A. Ornelas, AP

by Juan Carlos Llorca, Associated Press

by Juan Carlos Llorca, Associated Press

MIDLAND, Texas (AP) - Organizers of a parade in West Texas in which four U.S. military veterans were killed when a train plowed into a truck had been using the same route for three years, investigators said Sunday.

National Transportation Safety Board spokesman Mark Rosekind also announced that oilfield services company Smith Industries was the owner of the truck that served as the float the veterans were on during Thursday's parade in Midland.

Rosekind said the company was cooperating with investigators, who expect to interview the driver on Monday. The NTSB declined to release the driver's name.

Investigators have said the truck began crossing the train tracks even though warning bells were sounding and lights were flashing.

However, some Midland residents said they believe the signal time is too short. They say the guardrails aren't completely down by the time a train comes whizzing by.

"The signals come on and the arms go down, but before they are fully down, the train is already at the intersection," said Mark Thomas, who lives blocks from the track and says he crosses it daily.

"These signal times are unacceptable," Thomas added.

According to the NTSB, the warning system was activated 20 seconds before the accident, and the guardrail began to come down seven seconds after that. Everything functioned properly, Rosekind said, but investigators will have to check to make sure the signal timing met the requirements for that particular crossing.

The truck was the second of two parade floats filled with wounded war veterans. The first float had already cleared the tracks when the accident happened. Four veterans of Iraq and Afghanistan were killed and 16 more people were injured.

The parade was organized by a group called Show of Support-Hunt for Heroes and has been an annual event in Midland for nine years. It was supposed to be the start of a three-day weekend of banquets, deer hunting and shopping in appreciation of the veterans' service.

Rosekind said investigators were also looking at whether organizers had the proper permits for the parade.

"This is an entirely volunteer organization and activity, so there were a lot of things that were donated, and so that changes kind of the rules of what had to be filed," he said.

Midland is in Texas' oil-rich Permian basin, a region that has experienced a significant oil boom in recent years.

According to its website, Midland-based Smith Industries sells and manufactures oilfield service equipment. The website says the company provides steel and fiberglass tanks, separators, ladders, walkways and other equipment. The company has been in operation since 2000.

Smith Industries has a large facility and warehouse about five miles from the city. On Sunday, the business was closed. An American and Texas flag flew at half-mast and blue ribbons were tied around columns in a small parking lot. Large tanks, pipes, heavy machinery and trucks were scattered behind the gates.

Rosekind said the NTSB will conduct a sight test, probably Tuesday, to try to determine what the train engineer could see leading up to the crash. He said Smith Industries would likely provide a truck for the test.

According to the NTSB, the train sounded its horn nine seconds before the crash. The guardrail hit the truck, and then the engineer pulled the emergency brake, trying to bring the train that was traveling at 62 mph to a screeching halt.